/*
*    Qizx/open 3.0 beta
*
* This code is the open-source version of Qizx.
* Copyright (C) 2004-2009 Axyana Software -- All rights reserved.
*
* The contents of this file are subject to the Mozilla Public License 
*  Version 1.1 (the "License"); you may not use this file except in 
*  compliance with the License. You may obtain a copy of the License at
*  http://www.mozilla.org/MPL/
*
* Software distributed under the License is distributed on an "AS IS" basis,
*  WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
*  for the specific language governing rights and limitations under the
*  License.
*
* The Initial Developer of the Original Code is Xavier Franc - Axyana Software.
*
*/
using System;
using EvaluationException = System.Qizx.Api.EvaluationException;
using Node = System.Qizx.Api.Node;
namespace System.Qizx.XQuery
{
	
	/// <summary>	Provides access to context item, position and size.
	/// Passed to every eval method, and typically implemented by 
	/// expressions that modify the focus, namely Path and Filter.
	/// (internal use).
	/// </summary>
	public interface Focus
	{
		/// <summary> Gets current item position.</summary>
		long Position
		{
			get;
			
		}
		/// <summary>	Gets context size.</summary>
		long Last
		{
			get;
			
		}
		/// <summary>	Gets the current item.</summary>
		XQItem currentItem();
		
		/// <summary>	Gets the current item as an integer for optimization.</summary>
		long currentItemAsInteger();
		
		/// <summary>	Gets the current item as a double for optimization.</summary>
		double currentItemAsDouble();
		
		/// <summary>  Gets the current item as a String for optimization.</summary>
		string currentItemAsString();
		
		/// <summary>  Gets the current item as a Node for optimization.</summary>
		Node currentItemAsNode();
	}
}